<input type="text" id="reference_code" name="reference_code[]" required class="form-control" value="<?php echo set_value("reference_code"); ?>"/>
<input type="text" id="reference_code" name="re<input type="text" id="reference_code" name="reference_code[]" required class="form-control" value="<?php echo set_value("reference_code"); ?>"/>
<input type="text" id="reference_code" name="re